// Java Script数组是一个动态容量的哈希表
// 1. 长度可以变化，也无需连续
// 2. 类型可以不同
let arr = new Array(); //arr=[]
console.log(arr.length);
arr[0] = "Tom";
arr[1] = 18;
arr[2] = ["eat", "drink", "play", "happy"];

arr[-100] = 55000;
arr["position"] = "CEO";

console.log(arr);

